Melting apparatus



Dec. 26, 1939. A. J. GRINDLE MELTING APPARATUS '7 Sheets-Sheet l Filed Aug. l2, 1936 Dec. 26, 1939. A. J. GRINDLE MELTING APPARATUS Filed Aug. l2, 1936 7 Sheets-Sheetl 2 llaflllilnn Dec. 26, 1939. A, J GRlNDLE 2,184,297

MELTING APPARATUS Filed Aug'. l2, 1936 v'7 Sheets-Sheet 3 avr/2595 A. J. GRINDLE MELTING APPARATUS Dec. 26, 1939.

Filed Aug. l2, 1956 7 Sheets-Sheet 4 ZzUe/zor:

Jzlflggf @ra die By Dec. 26, 1939.

A. J. GRINDLE MELTING APPARATUS 7 Sheets-Sheet `5 Filed Aug. 12, 1.956

rzdle B Y Dec. 26, 1939. A. J. GRINDLE y 2,184,297

MELTING APFARATUS Inventor.'

De 26, 1939- A. J. GRINDLE MELTING APPARATUS Filed Aug. 12, 1936 7 Sheets-Shea*l 7 J il 30 mechanism.

Patented Dec. 26, 1939 PATENT lori-TCE MELTIN G APPARATUS Aubrey J. Grindle, Chicago, Ill., assignor to Alwin F. Pitzner, Winnetka, Ill.

Application August 12, 1936, Serial No. 95,523

Z1 Claims.

The present invention relates to improvements in melting apparatus for various metals, such for example as iron and steel, and has particular reference to a melting apparatus having a novel rotary furnace.

,Various objects reside in the provision in a new 'o and improvedmelting apparatus of one or more A of the following features:

1. A rotary furnace adapted for continuous or bath operation, and providing an elongated heating chamber having a large basin for the molten metal and a small outlet.

2. Power means for -supporting and rotating the furnace in an inclined position.

3. A plurality of burners within the heating.

Achamber arranged to provide efficient heating andy to locate the hottest zone substantially over the deepest portion of the molten metal.

4. A novel loading mechanism for 'throwing the material to be treated into one end of the furnace.

5. Means for supplying and uniformly distributing a preheated and intimately mixed fuel to the burner.

6. Stacks for both ends of the furnace to carry away gases, fumes and products of combustion.

7. Novel means for receiving the molten material from the furnace.

8. Interlock means for preventing interference between the fuelsupply means and the loading Numerous other objects reside in novel detail features of construction of the foregoing.

A general object is to provide a new and improved melting apparatus which is highly reliable, ecient in operation, which has a large capacity and low operating cost, and which is sturdy in construction. o

Further objects and advantages will become apparent as the description proceeds.

In the accompanying drawings,

o Figure 1 is a side elevational view, partially in vertical section, of a melting apparatus embodying the features of my invention.

Figs. 2 and 3 are fragmentary detail sectional views taken1 substantially along lines 2-2 and 3 3 of Fig. 1.

Fig. 4' is a plan view, partially in horizontal section, of the apparatus.

Fig. 5 isa fragmentarysectional detail view taken along line 5 5 of Fig. v4, and illustrating a fuel nozzle and mixer.

Fig. 6 is a transverse vertical sectional view the furnace forming part of the apparatus.

Fig. 'l is an enlarged elevational view of a fuel mixer at the inlet of the nozzle.

Fig. 8 is a diametrical sectional view of the mixer shown in Fig. 7.

Fig. 9 is a longitudinal vertical sectional view Fig. 12 is a fragmentary transverse sectional i view taken along line |2-I2 of Fig. 11.

Figs. 13 and 14 are perspective views of baille plates forming part of the distributor. Fig. 15 is a fragmentary View partially in vertical section and illustrating a loading mechanism for the furnace.

Fig. 1 6 is a sectional detail viewA of a coupling in the fuel supply line taken along line lli-I6 of Fig. 15.

Fig. 17 is a transverse Vsectional view of a control valve for the loading'mechanism.

Fig. 18 is a fragmentary detail view illustrating the valve operating mechanism.

Fig. 19 is a fragmentary detail view illustrating the valve operating mechanism in side ele-l vation.

Fig. 20 is a left end-elevational view melting apparatus.

Fig. 21 is a plan ladle.

,'Fig. 22 is a vertical sectional view of the ladle taken along line 22-22 of Fig. 21. f

Fig. 23 is a vsectional detail view taken along line 23-23 of Fig. 4. 4

Fig. 24 is a plan view of a metal receiving trough. Fig. 25 is a transverse vertical sectional view of the trough.

l Fig. 26 is a side elevational vview of the trough.

Referring more particularly to the drawings., the exemplary embodiment of the invention therein shown constitutes a melting apparatus adapted particularly for various metals, such for example as iron and steel, etc. In general, the

of the view of the Ametal receiving apparatus comprises a rotary melting furnace mechanism 30' for charging or catapulting theV metal or material to be melted into the inlet end of the furnace 28; and a fuel feeding mechanism 3| for supplying a suitable combustible airfuel mixture to the furnace 28.

The rotary melting furnace and drive The furnace 28 (see Figs. 1, 4, 6, 9 and 10, and

particularly Fig. 9) is elongated and mounted for rotation on its longitudinal axis. The interior thereof constitutes a heating and melting chamber 32 which has a restricted inlet throat 33 at one end, and the other end of which is conical and terminates in a restricted outlet or discharge opening 34. Preferably, the axis of rotation is slightly inclined out of the horizontal, with the inlet end of the heating chamber 32 uppermost. As a result, the charge indicated at A, tends to feed toward the discharge end, and the bottom of the chamber denes a shallow basin for the molten metal with a liquid line as indicated to the bottom edge of the opening 34. Thus, the basin extends substantially the full length of the chamber 32, and at the same time the opening 34 need only be large enough to permit the molten metal and slag to discharge. It is to be noted in this connection that the inclination is such that the molten metal extends substantially -up to the point a'.

In its preferred construction, the furnace 28 comprises an outer metallic casing or shell 35 lined internally with a suitable refractory material 36 having insulating properties. 35 consists of an intermediate section 3l which is cylindrical in form and adapted to be supported in a horizontally inclined position for a rotary drive, a conical discharge end section 38 having an annular end wall 33, and an inlet end section 48 in the form of an` elongated cylindrical duct and integrally connected by a short conical section 4I to the section 3l. Suitable gusset plates or braces 42 of varying length are provided to reinforce the shell 35 at the juncture between the sections 3l and 40. The section 38 is removable to permit lining and repair of the furnace 28.

The refractorylining 36 conforms to the interior of the shell 31, and over most of the area consists of an outer layer preferably of clay fire brick and an inner layer preferably of silica. At the discharge end, the lining 36 has a tubular extension 43 which projects through the wall 39 and which defines the opening 34, the outer end of the latter preferably being flared or rounded to facilitate pouring. A flanged ring 44 encircles the extension 43, and is removably bolted to the wall 39. The outer end portion of the tube 40, being somewhat removed from the hottest zone, is lined'with fire brick, and the inner end portion of the tube and the conical section 4l are lined with a thick layer of silica. To retain the refractory material in the tube 40, an annular plate 44a is secured to an outer peripheral flange 4|l*i on the tube, andoverlapsv the material.

The inlet throat' 33 is defined by the refractory lining, and is elliptical in cross-section as shown in Fig. 10.v It provides an outlet for fumes and gases of combustion, andan inlet for the iron, ore or other material to be treated or melted. The oval or elliptical form of the throat 33 causes the material to pass to thechamber 32 at the ends of the major axis. The material is preheated in the throat 33, and may in fact be partially or entirely melted therein before actually reaching the chamber 32.

To heat the furnace 28, one or more suitable burners 45 are mounted to discharge into the chamber 32. In the present instance, two powdered fuel burners 45 are mounted in the lined section 4l at opposite ends of the minor axis of 'the throat 33 in position to discharge a plurality of jets or streams of air-fuel mixture longitudinally into the Y/chamber 32. Each burner comprises a block46 which forms part of the refractory lining, and which is formed The shell' arenas? with an opening il flared at the inner end. A burner nozzle 48 of tubular construction extends into the outer end of the opening 4l, and is bolted to the shell section 4I. The burners 45 are adapted to be connected to a suitable supply of fuel as hereinafter described. By locating the burners 45 at the end of the minor axis of the throat 33, the solid or fluid material avoids passing directly thereover on its way into the chamber 32.

The burners 45 are relatively inclined in the longitudinal plane of the furnace 28 through the minor axis of the throat 33 so that the streams oi fuel mixture will converge symmetrically toward the axis of rotation. The preferred degree of inclination is determined by a number of factors. Thus, it is desirable that the flames converge at a point as near as practicable tothe discharge end so that the hot gases of combustion will be deflected and caused to travel back over the metal. At the same time, the flames should not strike the surface of the molten bath before combustion is fairly complete. Also, it is desirable that the point at which the flames converge be located substantially over the deepest portion of the molten metal. 'I'he taper of the lined section 38 serves to locate the deepest point of the metal near the hottest point of the furnace chamber 32.

In operation, the material being treated is heated directly by the products of combustion which reverse in flow and pass out through the throat 33. Also, the refractory lining 36 becomes highly heated, and in the rotation of the furnac 28 serves to heat the material.

The furnace 28 may bev supported by any suitable means for a rotary drive. In the present instance, this means comprises a rectangular supporting frame 49 which is mounted in an inclined position on an elevated base 50 on a stationary foundation 5I. in upstanding brackets 52 on the frame 49 at opposite sides of the shell 35 are a plurality of I rollers 53. These rollers respectively engage peripherally with two circular rails 54 encircling and secured to opposite ends of the intermediate section 3l of the shell 35, and thereby serve to support the latter. The large end of the conical shell section 38 has an outer peripheral ange 55 which is removably bolted to the lowermost rail 54 to complete the shell assembly. Mounted in the upper end portion of the frame 49 is a thrust bearing 56. A thrust roller 5l is journaledin the bearing 56 on a generally vertical axis, and engages the lower side of the uppermost rail 54 to support the shell 35 against endwise movement, and particularly to maintain the rollers 53 and the rails 54 in proper engagement.

The rotary drive (see Figs. 1, 4 and 10) for the furnace 28 is transmitted to the rails 54 through frictional engagement with the rollers 53 at one side which are fixed on a common drive shaft 58. This shaft is connected through gears 59 and 60 to a variable-speed transmission 6| driven by an electric motor 62.

The discharge end ofthe furnace 28, and particularly the refractory extension 43 projects through an opening 63 in one side of the base 64 of a stack 65 which serves to carry away fumes from the metal and also any products of combustion that may escape through the opening 34. A plurality of openings 66 with removable Covers 61 are provided in the stack base 64. One of these openings 66 (see Fig. l) is substantially in axial alignment with the opening 34 and is Rotatably supported therefore conveniently available for charging the furnace by means of a spoon (not shown) with alloys or petroleum carbon or other materials for changing the analysis or composition of the nished product. The other openings 88 are located at the opposite sides of the extension 43, and aiords access for various purposes, such for example as the removal of slag tending to clog the discharge opening 34.

The stack '65 is supported in elevated position by means of hanger bars 68 Isuspended from a suitable support, such as a roof88, and the base 6 4 is flared downwardly and open at the bottom to permit the metal discharging from the opening 34 to pour into a suitable container 18. In the present instance, the container 18 is shown as a large. steel ladle or bucket having a discharge spout 1|, and pivotally mounted by means of trunnions'12 on a truck 13 (see Figs. 21 and 22). The truck 13 is adapted to .be moved on suitable tracks 14 in the foundation v8| into position beneath the stack base 64. To provide l means for swinging the ladle10, a large gear 15 is xed on one of the-trunnion shafts, and meshes with a pinibn 16 on a shaft 11 .journaled in the frame of the truck 13 and having a hand wheel 18 fixed thereon. It will be understood that the container 18 is utilized for continuous furnace operation.A

'I'he furnace 28 also is provided with a discharge opening 18 in the wall of the lined shell section 38 adjacent the deepest point of the metal. This opening is primarily intended to discharge the metal at the end of a batch operation, and normally is closed by a plug 88. However, it' may also be used during Va continuous operation, the plug 88 in this case being withdrawn.

Mounted beneath the furnace 28 to receive metal from the opening 18 when the latter is in its lowermost position is a trough 8| see Figs. 1, 9 and 24 to 26). The trough 8| may be supported on a' suitable frame 82 on theIoundation and in its preferred form is open'at the top throughoutits length and extends transversely of the furnace 28 to underlie the entire lower course of thepath of the opening 18. Prefer- \ably, the walls of the'tr'ough areclosed at the bottom, sides and ends, and consist of an outer 50 metal casing`83 lined with a suitable refractory material 84. In cross-section (see Figs. 9 and .25), the trough 8L is somewhat constrictedat the top, and the upper inside edges ofthe materia] 84 are rounded. Two parallel upstanding guard plates 85 are secued respectively to opposite sides of the trough 8|, and at their upper edges conform closely to-the curvature of the shell section 88 at opposite sides of the opening 18. The lower edge portions of the plates 85 rest on the side walls of the trough 8|, and are struck inwardly to define inclined guides 88 for directing stray metal into the trough opening: The trough 8| is vertically inclined from end to end, and is provided at its lowemost end with a discharge spout 81 of the same. general construction. Preferably, the spout 81 is horizontally inclined to extend at an angle of approximately-45? to the "furnace axis into a convenient position over a receiving'bucket or ladle 88.

The outer end of the duct 48 extends through a flanged opening `88 in the enlarged base 88 of a stack 8| for carryingl away gases, `fumes and products of combustion from the furnace 28. The base 88 is open at the bottom and mounted in elevated position'on a support. consisting of a plurality of I-columns on the foundation 5|. The support 92 is open between the I-columns at the sides and adjacent the furnace 28, and has a wall 83 closing the space'between the columns remote from the furnace.

The charging mechanism 'me charging mechanism an (see Figs. 1 to 4,

and 17 to 19) is mounted belowthe stack 8| in position to introduce the material to be treated into the open end of the duct 48 within the stack base 88. -In its preferred construction, the

charging mechanism 38 comprises an open upright frame 84 which is mounted on the foundation 5|, and supported in a positionslightly inclined from the vertical and substantially in the plane of the inlet end of the duct 48. Suitable struts 85, anchored to the elevated base 58, are provided as auxiliary supports for the frame 84.

Mounted on a horizontal rock shaft 88, extending transversely of the furnace 28 and journalled in bearingS brackets 81 on the frame 84 is a swinging arm 88. A charging bucket 88 is rigid with 'the free end of the arm 88, and is adapted to be oscillated or sw i thereby from 'an idle or filling position into an elevated position directly in line with the open end rvof the duct 48 as illustrated in Fig. 15. The idle position is defined by a stop or rest |88 on the foundation 5| for engagement by the bucket 81. When in idle position,.the bucket v81 directly underlies a chute |8| moimted in and opening through the wall 83. The elevated position is determined by engagement of an impact head |82, mounted in an intermediate portion of the arm 88, with a fixed stop or plate |83 on the upper endv of the frame 84. The head |82 (see Fig. 3) preferably consists of. a plunger urged outwardly into an extendedv position by a coiled compression spring |84. In its upward movement, the arm 88 comes to a sudden stop when the head |82 engages the plate |83, thereby causing the material in the bucket 88 to be thrown or catapulted into the duct 48. v

To provide power means for actuating the bucket 88,' the pivoted end portion/` of the yarm 88 is formed with a concentric arcuate segment |85 (see Fig. 2) with a. peripheral -groove |88.

A rope or cable |81 extends alongv the groove |86,

and is securely anchored at one end to the arm pressure, may be supplied under the control of a valve ||2 (see Figs. 17 to 19) to the cylinder |88 to elevate the bucket 88, and subsequently relieved to permit return of the bucket under the forceof gravity into idle position. The valve ||2 comprises a body ||3 havinga bore ||4 with peripherally spaced ports ||5 to H8'. The upper port ||5 is open to a pipe ||8 which may be connected to any suitable source of compressed 'air `(not shown). The side ports ||6 and ||1 are connected to two pipes |28 and |2| leading respectively to opposite ends of the cylinder |88. 'I'he lower port ||8 is connected to a pipe |22 opening to the atmosphere in the stack base 88. Rotatyreduces the required lifting power.

ably adjustable in the bore 4 is a valve member |23 having an actuating shaft |24 and having diametrically opposed land areas |25 and |26 defining intermediate peripheral spaces |21 and |28. Two oppositely extending levers |29 and |30 are fixed on the shaft |26, and carry suspended chains |3| by which the valve may be actuated manually. v

The valve member or plug |23 is normally held in neutral position in which the land areas |25 and |26 block the ports H5 and H8. The means for this purpose comprises a tension spring |32 which is anchored at one end to the pipe ||9 and which is connected at the other end to an intermediate chain link |33 anchored at opposite ends to the levers |25 and |30. In operation, when the vvalve member |23 is rotated out of neutral in a clockwise direction, air will be supplied freely tothe pipe |20 and the pipe l2! will be connected to the unrestricted exhaust, thereby causing the bucket 99 to be elevated rapidly until the head |02 impinges against the stop |63. Movement of the valve member |23 in a counterclockwise direction past neutral position will connect the pipe |2| to pressure and the Ipipe |20 to exhaust to lower the bucket 99. In this position, the land area |26, which is wider than the area |25, covers the port H6, but establishes the exhaust connection through a restricted bleed passage |36 adapted to throttle the discharge from the pipe |20 so as to cause the return movement of the bucket 59 to be comparatively slow.

To facilitate ease of operation, a counterweight |35 is fixed on the shaft 95. When the bucket 59 is in idle position, the counterweight |35 is located at the opposite side of the shaft 96, and When the bucket 99 is in elevated position, the counterweight is located forwardly of the shaft 95, and serves to overcome any tendency of the bucket to stay up.

Fuel feeding mechanism The fuel feeding mechanism 3| (see Figs. 3 to 5, 7, 8, 10 to 16, 20 and 23) is adapted to supply a mixture of powdered fuel and air to the burners 45 in all positions of rotation' of the furnace 26. The fuel, such as coal, is supplied from a hopper |36 to a pulverizer |31 which is not shown in detail since per se it forms no part of the present invention. It is sufficient to say that the pulverizer |31 has two outlet ducts |38 and |39 of which the flrst discharges a primary mixture of air and suspended or entrained powdered fuel at a definitely maintained velocity, and the latter is adapted-to supply a variable amount of secondary air. e

The air entering the pulverizer |31 is preheated by the gases in the stack 9|. To this end, the stack 9| is of double-walled construction to define a peripheral air space |40 open at the lower end to receive air from the atmosphere.v The upper end vof the space |40 opens to an enlarged annular chamber or bustle |4I, near the top of the stack 9|. A vertical duct |42 leads the air from the chamber |4| to the inlet of the pulverizer |31. Preheating the air reduces the power required to operate the pulverizer |31, and also dries the powdered coal and renders it more friable.

The air duct |39 has a conical mixing and induction throat |43 (see Fig. 23) at the discharge end, and is connected through an expansion and swivel joint |44 (see Fig. 16) to a fuel duct |45 extending through the base 90: of the stack 9| maar to the furnace 28. The primary fuel duct, |30 is connected to the duct |39 to discharge axially into the throat |63 to complete the ultimate fuel mixture. By supplying the primary mixture separately of the secondary air, adequate air velocity for entraining the fuel is always maintained regardless of variations in the total volume of air in the ultimate mixture.

The expansion and swivel jointml comprises an outer sleeve |56 bolted to the discharge end of the duct |39 and supported from the stack 9| by a plurality of hanger bars |61. The inlet end of the duct |65 telescopes slidably and rotatably into the sleeve |66. A suitable packing |58 is confined between the duct |45 and the sleeve |66 by an adjustable gland |69.

The duct |65 extends through an opening |50 into the stack base 90, and is connected at its discharge end to a distributor |5| (see Figs. l1 to 14) mounted on one side of the duct 40 of the furnace 28. It will be evident that the fuel mixture will be highly preheated in passing through the duct |65. By preheating rst the air as described, and then the fuel mixture, a substantial heat reclamation and economy is .effected, and the subsequent combustion of the fuel is quicker and more emcient.

In its preferred form, the distributor |5| comprises a closed rectangular housing |52 mounted in a bracket |53 on one side of the duct 40. The outlet end of the duct |65 is enlarged to rectangular form and clamped to the bracket |53 and opens to the housing |52. The latter has two relatively inclined outlet sleeves |56 and |55 which in effect constitute a forked discharge. To insure a uniform distribution of the fuel mixture to the sleeves |56 and |55, a plurality of alternate baille plates |56 and 51 are secured in nested relation on a tie bolt |58 in the bracket |53. The plates |56 and |51 are flat, and formed with side flanges |59 and |59a to effect the proper spacing and t0 define a series of parallel passages. Of the plates |56, the flanges |59 are elongated and inclined to extend intothesleeve |56, and hence to direct the fuel mixture passing through the associated passages entirely to the sleeve. The flanges |59 of the plates |51 are similar in form, but inclined to direct fuel mixture to the sleeve |55. The sleeves |54 and |55 are connected respectively by flexible tubes |60 to the two burner nozzles 48.

prises a circular disk |62 which is bolted at the peripheral margin between outer peripheral flanges |63 on an expanding cone member |66 and a cone member |65 at the inlet of the nozzle 48. Two concentric sets of peripherally spaced vanes |66 and |61 are formed in the central portion of the disk |62. The vanes |66 and |61 are twisted respectively in opposite directions to extend at both sides out of the plane of the disk, and hence create a high degree of turbulence.

It willbe evident that in the rotation of the furnace, the duct |45 will be revolved thereby about the axis of the coupling |44. vLongitudinal expansion and contraction of the duct |45 are permitted by the coupling |44.

To prevent interference between the charging apparatus 30 and the duct |45, means is provided for preventing clockwise adjustment of the control valve ||2 except when the duct is passing through the upper course of its orbital movement. In the present instance, this means comprises a rotary cam |68v (see Figs. 18 and 19) xed on the duct |45 and adapted for engagement' with a roller |69 on the free end of the arm |29. The cam |68 has an arcuate face extending approximately through 180, and adapted to hold or depress the arm |29 into neutral position. Down-A ward movement is permitted, but this will not eiect elevation of the bucket 99. The other half ofthe cam |68 has an arcuate face of -a smaller radius, and when disposed over the arm |29 permits free adjustment of the valve H2 into any selected position.

While I have disclosed the invention as applicable particularly to the melting of metals, it is to be understood that the invention may be utilized for treating various kinds of materials not necessarily involving melting.

I .claim as my invention:

1. In a heating apparatus, a rotary furnace comprising, in combination, an elongated outer wall lined internally with refractory material and defining a heating chamber having an inlet at' one end and a discharge opening at the other end, burners mounted in said wall eccentrically of the axis of said furnace for movement therewith and opening to said chamber, means for supplying fuel to said burners in all positions of rotation of, said furnace, and power means vfor rotating said furnace continuously in one direction.

2. In a heating apparatus, a rotary furnace comprising, in combination, an elongated outer wall mounted for rotation on a vertically inclined axis and lined internally with refractory material,

the interior defining a heating chamber enlarged intermediate its ends, with an elongated inlet throat of reduced size at the uppermost endu and 'a discharge opening of reduced size at the other inlet throat of elliptical cross-section at the upper end and a discharge opening at the other end, a plurality of burners spaced about said throat for heating the interior of said furnace,

r and means for rotating said furnace.

. ber, and means for rotating said furnace.

mounted in said wall at opposite ends of the 5. In a heating apparatus, a rotary furnace comprising, in combination, an elongated outer wall mounted for rotation on a vertically inclined axis and lined internally with refractory material, the interior defining a heating chamber enlarged intermediate its ends, with an inlet throat of elliptical cross-section at the upper end and a ischarge opening at the other end, two burners minor axis of said throat to heat said chamber and inclined toward each other ,to discharge con'- verging streams of fuel mixture along the axis of rotation toward said discharge opening, and means for rotating said furnace. y

6. In -a heating apparatus, a rotary furnace comprising, in combination, an elongated outer wall having an intermediate substantially cylindrical section, a conical section on one end terminating in a relatively small coaxial discharge opening with an outwardly flared pouring edge, a conical burner block section merging into the other end of said cylindrical section, and an elongated inlet duct defining an inlet throat of elliptical cross-section and opening through said burner block section, the interior of said wall being lined with refractory material and defining a heating chamber adapted to contain a bath of the material to be treated, said furnace being vertically inclined'with the inlet duct at the uppermost end ofthe axis of rotation whereby said bath 'has a deep point intermediate its ends and a liquid line extending from said burner block section to said discharge opening, two burners mounted in said burner block section at opposite ends of the minor axis'of said throat, and being inclined to discharge converging streams of fuel mixture along the axis of rotation toward said discharge opening with the point of juncture substantially over said deep point, and means for rotting said furnace.- i

7. In a heating apparatus, in combination, an elongated rotary furnace having an enlarged cylindrical portion intermediate its ends, two rails encircling opposite ends of said portion, a

lvertically inclinedunitary supporting frame, a

plurality of rollers journaled on said frame, and

engaging the peripheries of said rails to support said furnace for rotation on a vertically inclined axis, a roller journaled in said frame between said rollers and engaging the lowerrside of the uppermost rail to locate said furnace axially, and means for driving certain of 'said rollers to rotate said furnace. e,

8. In a heating apparatus, in combination, a vertically inclined rotary furnace having an inlet at its uppermost en d and a discharge adjacent its lowerrnost end, a vertical stack receiving said inlet end and adapted to direct fumes, gases and other products of combustion therefrom, a stack receiving said discharge end of said furnace,l a ladle removably mounted beneath said last mentioned stack to receive treated material from said furnace, power actuated means for catapulting material to be treated into the inlet end of said furnace, means for heating the interior of said furnace, and a powdered fuel apparatus for supplying a preheated fuel mixture to said heating means.

9. In a rotary heating apparatus, an elongated rotary furnace mounted on a vertically inclined axis and having an internal heating chamber comprising an intermediate coaxial cylindrical portion and a lower end coaxial conical portion, an inlet at theuppermost end Aof said chamber, means defining an axial outlet at the apex of said conical portion for discharging treated material in a continuous operation, the interior of said chamber at. the juncture of said cylindrical and conical portions extending below said outlet to contain a bath of material adapted to be heated by the refractory in the rotation of the furnace, and a normally closed supplemental outlet opening through the wall of said furnace for dischargin'g'material from the depest point of said bath.

10. In a rotary heating apparatus, in combination, a rotary furnace having an inlet at one end and an outlet at the other end, a double walled stack communicating with said inlet and defining a peripheral air space and opening at the lower end to the atmosphere, a fuel pulverizer having a fuel inlet and an air inlet, means for connecting the upper end of said air space to said air inlet, means for supplying an air-fuel mixture from said pulverizer to said furnace, said last mentioned means including a fuel duct extending transversely through said stack.

11. In a heating apparatus, in combination, a rotary furnace having an inlet at one end and a discharge adjacent its other end, a double walled vertical stack receiving said inlet and adapted to direct fumes, gases and other products of combustion therefrom and defining an air space open at one end to the atmosphere, power actuated means for introducing material to be treated into said inlet, burner means for heating the interior of said furnace, and means for supplying an air- 'fuel mixture to said burner means and having an air intake connected'to the other end of said air space.

12. A heating apparatus comprising a rotary vfurnace having an inlet at one end, burner means mounted on said furnace for movement therewith and to discharge a mixture of fuel and air thereto, a source of fuel having an outlet line, a fuel duct having a swivel joint at one end with said line in axial alignment with said furnace and attached at the other end to said furnace for orbital movement, means connecting said duct to said burner means, power operated means for charging material to be treated into said inlet and including a control member, and cam means rotatable with said duct and cooperating with said control member to prevent operation of said power means when said duct is located in the course of movement crossing the pathof said charging means.

13. A rotary melting apparatus comprising a rotary furnace having an inlet at one end,burner means mounted on said furnace-for movement therewith and to discharge a mixture of fuel and air thereto, a source of fuel having an outlet line, a fuel duct having a swivel and expansion joint at one end with said line in axial alignment with the furnace and attached at the other end to said furnace for orbital movement, means connecting said duct to said burner means, and power operated means for elevating material to be treated into said furnace.

14. In a heating apparatus comprising, in combination, a rotary furnace, means for supporting said furnace for rotation, means for rotating said furnace continuously in one direction, a powdered fuel burner having an inlet line and mounted on said furnace for movement therewith and to dis- Charge an air-powdered fuel mixture thereto, and a fuel mixer interposed in said line at the lnlet of said burner, said mixer comprising a peripherally held disk formed with a plurality of concentric sets of oppositely twisted vanes.

15. In a rotary heating apparatus comprising, in combination, a rotary furnace, two powdered fuel burners mounted on said furnace for movement therewith and to discharge an air-powdered fuel mixture thereto, a fuel mixer interposed in the inlet of each burner, a fuel supply line, and a distributor for connecting said line to said burners, said distributor having a housing with two relatively inclined discharge sleeves, a plurality of nested baiiies in said housing and formed with anges adapted alternately to direct fuel from said line respectively to said sleeves.

16. In a rotary heating apparatus comprising, in combination, a rotary furnace, power means for rotating said furnacecontinuously in one direction, powdered fuel burners mounted on said furnace for movement therewith and to discharge an air-powdered fuel mixture thereto, a fuel mixer interposed in the inlet of each burner, a fuel supply line, and a distributor for connecting said line to said burners and including means for uniformly proportioning the fuel to said burners.

17. In a heating apparatus, a rotary furnace on a generally horizontal axis and having a discharge opening in its peripheral wall, a narrow trough extending transversely of and underneath the lower course of movement of said opening, and upstanding guard plates on the sides of said trough and conforming generally to the curvature of said furnace so as to direct the discharge from said openingtinto said trough.

18. In a heating apparatus, a rotary furnace comprising, in combination, an elongated outer wall mounted for rotation on the vertically inclined-axis and lined internally with refractory material, the interior defining a heating chamber enlarged intermediate its ends, with an inlet throat of elliptical cross section at one end, two burners mounted in said wall at opposite ends of the minor axis of said throat to heat said chamber, and means for rotating said furnace, the material passing through said throat tending to ow therethrough at the oppositel ends of the major axis of said throat.

19. fn a heating apparatus, in combina/tion, a vertically inclined rotary furnace having an inlet at its uppermost end and a discharge adjacent its lowermost end, a vertical stack receiving said inlet end and adapted to direct fumes, gases and other products of combustion therefrom, power actuated means for catapulting material to be treated into the inlet end of said furnace, means for heating the interior of said furnace, and means for supplying a preheated fuel mixture to said heating means.

20. A heating apparatus comprising a rotary furnace having an inlet at one end, burner means mounted on said furnace for movement therewith' and to discharge a, mixture of fuel and air thereto, a source of fuel having an outlet line, a fuel duct having a swivel joint at one end with said line substantially in axial alignment with said furnace and attached at the other end to said furnace for orbital movement, means for connecting said duct to said burner means, and drive means for rotating said furnace.

21. A heating apparatus comprising -a rotary furnace having an inlet at one end, burner means mounted on said furnace for movement therewith and to discharge a mixture of fueland air thereto, a source of fuel having an outlet line, a fuel duct having a. swivel joint at one end with said line in axial ailignment with said furnace and attached at the other .end to said furnace for orbital movement, means connecting said duct to said burner means, power operated means for charging material to be treated into said inlet and including a control member, and means coacting with said control member to prevent operation of said power means when said duct in the course of orbital movement is crossing the path of said charging means.

AUIBREY J. GRINDLE. 

